Intravenous and Intraosseous Catheter Placement in the Companion Animal

Kimberly Baldwin, LVT
Education Coordinator
Cornell University
Ithaca, NY

 

The purpose of this lecture is to allow the technician to become familiar with the many different types, materials, techniques and considerations for setting up and placing intravenous catheters in the Companion Animal

Patients entering the hopital must be evaluated for the individual needs before placing an intravenous catheter. Some considerations are:

1.  What is the primary problem of the patient?

-Shock, Blood Loss, Difficulty Breathing, Vomiting, etc

2.  What are the needs of the patient?

-Fluid Therapy, Intravenous Medication, Sample Collection, Anesthesia

3.  What is the disposition of the patient?

-Calm, aggressive, minimal restraint, can you work with the patient after the catheter is placed?

4.  How long will the patient need to utilize the catheter?

-HBC, Diabetic, Pancreatitis (possible TPN), Liver Dz.

There are many types of catheters presently available. The three techniques for placing catheters that we will discuss in this workshop are:

1.  Through the needle

a.  This type of catheter feeds the catheter through a sterile needle

b.  Examples are Venocath, Delmed, Intracath

2.  Over the needle

a.  This type of catheter can be fed off the needle

b.  Examples are Insyte, B & D, Peel - a - ways, PICCs

3.  Sheldinger technique

a.  This type of catheter requires a five step technique

b.  Examples are central line catheters single - tri-lumen

Catheters are made up of many different types of materials. Before placing an intravenous catheter the duration of the catheter should be considered before choosing the catheter type to be used. Some examples of material are:

1.  Silicone - This is the least reactive of materials and can be very flexible. Ideal for long term use and central venous access.

Examples are single - tri-lumen. Manufacturers are Mila International, Braun, Arrow, Cook Veterinary Products.

2.  Polyurethane - This is a common material that is soft and flexible. Good for long term use.

Examples are peripheral and central line catheters. Manufacturers are Mila International, Cook Veterinary Products, Arrow

3.  Polyvinyl Chloride(PVC) - This is a somewhat rigid material and can cause moderate reactivity.

Examples are central line catheters- Delmed Inc. -through the needle catheter

4.  Teflon - This is another common material. It is a very rigid material and will thrombus vessels with long term use. Seen most commonly in peripheral catheters. Manufacturers are Insyte, Abbocath, Venocath

Restraint and positioning is key to successful catheter placement. Most animals are best restrained in lateral recumbancy. If central venous pressure is a consideration the animal should be placed in left lateral recumbancy for catheter placement in the right jugular vessel. The catheter should rest at the anterior vena cava or just cranial to the right atrium. Sternal recumbancy can be used for overweight or dyspneic animals. Cats sometimes prefer this position also. Additional assistance may be needed for appropriate restraint for sternal recumbancy. A towel under the neck may be used on animals with thick necks or poor venous return.

Steps for placing a through the needle catheter in the jugular vein

1.  Place the animal in the position of choice. Preferable lateral recumbancy

2.  Restrainer is responsible to restrain the animal without movement and hold off the jugular vein

3.  Clip and complete a sterile preparation on the desired area. A 2 x 2 area is generally recommended. Slightly trim hair around neck for better placement of tape if animal has long hair. Ex. Samoyed, Old English Sheepdog, etc

4.  Sterile gloves should be worn for all catheter placement whenever possible.

5.  Tent the skin and place the needle under the skin on top or along the side of jugular vessel. This should be done at a 30 - 45% angle. NO MORE!

6.  Once the needle is under the skin palpate the jugular vessel and advance the in the vessel utilizing the same angle. Be assertive but REMEMBER only the tip of the needle needs to be seated in the vessel. Beginners usually go through the vessel. If this is a possibility, slowly back out the needle from the vessel checking for a flashback with every movement. The biggest mistake that occurs at this point is individuals move to quickly with the needle once under the skin and they do not observe a flashback.

7.  Take time to palpate where the needle and vessel is then re-advance your needle as necessary. A short quick motion is needed to seat the catheter in the vessel.

8.  Look for a flashback in the catheter line. If an animal is dehydrated or in shock a flashback is not always seen. You may try to advance the catheter without a flashback if you palpate catheter and vessel to be in the same place. If the catheter advances without resistance you are most likely in the vessel.

9.  When advancing the catheter down the clear sheath, go to the end of the catheter and use your index finger and thumb to push the catheter through the needle and into the vessel. The other hand should always hold the needle in place.

10.  Advance the catheter until it is seated in the needle hub.

11.  The needle can then be removed from the vessel and the restrainer should hold off at the venipunture site to create homeostasis. The needle guard or cap should be placed over the needle and closed as soon as the needle advances out of the skin. Use caution not to move the catheter back and forth out of the vessel once the needle appears out of the skin.

12.  Once the needle is covered with its protective guard a twisting motion being careful not to pull the catheter out when pulling the sheath off should remove the clear plastic sheath. Samples can then be taken out of the catheter and a heperinized flush should be used to keep the catheter patent. The restrainer should not let up from the venipuncture site until homeostasis has occurred.

13.  T-Connectors are very useful for jugular catheters because they omit the strain of the extension set.

Trouble Shooting

If the animal is dehydrated has acute blood loss, or in shock you may not get an adequate flashback to confirm you are in the jugular vein. If the catheter feeds through the needle well initially (approximately half of the catheter length) then stops, it may be necessary to feed the catheter off the stylet and feed it into the vessel.

Other suggestions would be to extend the head slightly or move the front legs back or forward. This works especially well for cats. An x-ray to determine location of the catheter may be required if the technician is uncertain of the placement of the catheter and CVP measurements are required.

If an x-ray determines that the catheter has been placed within the right atrium the catheter will need to be backed out of the vessel, looped, then secured to the body wall with a small 1inch piece of porous tape and glue.

Catheter wrapping

The following instructions are recommendation for catheter security. Modifications of these techniques may need to be made pending the individual animal and catheter type used.

You will need:

1" porous tape glue(vetbond) or suture

2" cast padding small 1/2" gauze square

2" gauze cling betadine or triple antibiotic ointment

2" Vetwrap heparinizd flush

We use .7ml of 1,000USL heparin per 100ml .9% Sodium Chloride bottles. A new bottle or bag should be made up daily. We then draw flushes up in 3cc syringes for catheter flushing purposes.

1.  Three pieces of tape should be cut to the length of the needle guard. A fourth piece of tape should be cut for the length of tape needed to go around the animal's neck.

2.  Two short pieces of tape are used to cover the needle guard. One on each side of the guard starting at the bottom of the guard and extending to the point where the catheter is seated into the guard. It is important not to place tape on the T-Connector or extension set so that you may replace them as necessary.

3.  The third piece of tape is used at the bottom of the needle guard closest to the neck at a 90-degree angle from the guard. A tab is made from each end of the tape that is extending beyond the needle guard.

4.  The catheter is then turned 45 degrees so the needle guard is turned dorsal, seating the needle guard a distance behind the animals ears for the comfort purposes.

5.  The catheter should be aspirated and flushed again before being glued or sutured to determine appropriate positioning of the catheter. The catheter is then secured to the neck with glue or suture to the tape at the catheter site. Make sure there are no kinks at the site of the catheter before using glue or suture. If using glue place a drop on the backside of the tape closest to the body wall on each side of the catheter guard. Another drop of glue should be placed on the back of the needle guard. The needle guard should be pressed against the body wall. One last drop of glue should be placed where the catheter hub seats into the needle guard to prevent the catheter from slipping back out of the needle guard.

6.  A small amount of triple antibiotic ointment should be placed at the venipuncture site and a small gauze square should be placed over the site.

7.  The long piece of tape should have a V slit made in one end of the tape approximately 2" long. The slits are placed on each side and behind the needle guard. The rest of the tape should be used to go around the neck of the animal. It may be necessary to use an additional piece of tape to loop around the other side of the neck and needle guard.

8.  Cast padding is then used to add comfort to the animals wrap. It should be wrapped around the neck at each side of the catheter guard in continues motion.

9.  Gauze cling is then used in the same manner as cast padding.

10.  Vetwrap is used last with the same technique to hold the catheter in place

11.  The end of the T-Connector farthest from the needle guard is then taped to the bandage.

12.  The catheter should be aspirated and flushed with a SMALL amount of heparinized saline in between each layer of wrap to assure the catheter has not moved between layers of wrapping.

Catheter Care

Catheters should be re-wrapped on an as needed basis. All catheters should be looked at if the paw is swollen, bandage is soled or if the animal is consistently shaking paw or reacts negatively to injections. It is important to have another intravenous catheter in place before removing initial catheter.

T-Connectors should be replaced approximately every three days and should be done when you are rewrapping the catheter.